Conventional video signal processing systems usually incorporate mechanical devices such as potentiometers and switches to set certain system parameter adjustments such as oscillator frequency, genlock frequency range and phase offset. In many cases, the potentiometers and switches may be used to preset the system parameters at the factory where the video processing system is manufactured. The potentiometers and switches, however, may not be located in a manner which permits customers and service personnel easy access to the potentiometers and switches once the video processing equipment is installed at a customer site. Thus, field adjustment of the system parameters may require the movement or partial disassembly of the video processing system to permit a service technician or customer access to the potentiometers and switches. As a result, field adjustment of the system parameters can sometimes involve a great deal of effort.
In view of the above, it would be desirable to provide a system which permits certain system parameters to be electronically adjusted without requiring access to numerous potentiometers or switches. The provision of electronic adjustment would greatly simplify the adjustment procedure and allow the genlock circuit parameters to be readily adjusted in the field by service technicians or customers.